通過2,2,6,6-四甲基-1-哌啶基氧基自由基（TEMPO）-氧化法製備纖維素奈米纖維，並將其命名為TOCNF。通過電導滴定法測定TOCNF的羧基含量，並根羧基含量準備了一系列的比例（NH2 / COO-）= 0、1.0、2.0、3.0和4.0。樹枝狀分子(Polyamidoamine (PAMAM) dendrimer)通過與TOCNF產生化學鍵結，形成交聯凝膠。通過傅里葉變換紅外吸收光譜檢查確定了醯胺鍵的形成，並測量了ζ電位的pH依賴性，以確定製備膜的凝膠形成的最佳條件。
薄膜的溶脹度和水氣吸附透露出NH2 / COO- = 2.0具有較高的交聯度。乾/濕拉伸試驗則讓我們了解到交聯後的薄膜變得更加堅韌並提高了耐水性。交聯後仍保留了薄膜本身的高透光性，並且熱穩定性提高。上述測量足以證實了交聯的水凝膠膜具有更好的機械性能，同時保持高透明性和熱穩定性的增加。

Cellulose nanofibers were prepared by 2,2,6,6-tetramethyl-1-piperdinyloxy free radical (TEMPO)-oxidation process and named TOCNF. The carboxyl content of TOCNF was determined by the conductivity titration method. According to the carboxyl content, we prepared series of ratios (NH2/COO-) = 0, 1.0, 2.0, 3.0 and 4.0). The amine-terminated dendrimer (generation 0) was attached to the TOCNF by amide linkage to form a crosslinked gel. The amide bond formation was checked by Fourier transform infrared absorption spectroscopy. The pH dependence of zeta potential was measured to determine the optimum condition of gel formation, where films were prepared.
Both swelling process and vapor adsorption of films indicated that the ratio NH2/COO- = 2.0 had higher crosslink degree. Dry/wet tensile test referred that films became more tough and increased the water resistance after crosslinking. The high transmittance of the film was still remaining and the thermo stability was increased after crosslinking. The above measurements confirmed that the crosslinked hydrogel films have better mechanical properties, remaining high transparency and increased thermal ability.

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